To maintain quality in the manufacture of electrical circuits, it has always been desirable to perform various functional and parametric tests on the circuits prior to their use or sale. This has become increasingly difficult with the advent of photographic processes for manufacturing integrated circuits and their associated electrical contact. In this regard, such integrated circuit contacts, which are typically formed with aluminum, on wafers of silicon substrate material, are very small and tightly spaced. In fact, points on the circuit which would typically be contacted to perform the various tests may have dimensions of less than 2 mils. To compound the problems associated with providing electrical contact with these points, the aluminum material of the contact points has oxidized to provide an insulated coating. It has been desirable to penetrate this oxide coating in order to provide an adequate electrical contact with the particular contact point.
Probes of the prior art have typically been held stationary while the integrated circuit chips have been moved to provide electrical contact between a particular one of the contact points and the tip of the probe. The relative movement between the probe tip and the contact point has been slow so that the testing apparatus have relied upon a relatively constant force, such as ten grams to penetrate the oxide coating and provide contact with the contact point. The ten grams of force has been sufficient in some cases to penetrate the oxide coating but the same ten grams of force has ultimately been exerted upon the contact point so that the point has been cut or otherwise deleteriously affected by the test. For this reason, reprobing of a particular integrated circuit has not been advisable. Some of the probes have been provided with a tip which has been moved laterally across the oxide coating to facilitate the penetration thereof. This movement has also adversely affected the integrated circuit by scratching the particular contact point.
Therefore, it would be highly desirable to have a new and improved probe, which is relatively inexpensive to manufacture, and which develops a sufficient force to break through a thick layer of oxide coating and to dissipate it from the exposed electrical contact.